Hearing aid



June5,1945. R. s. WYCKOFF 222311739 HEARING AID Filed June 26, 1942INVENTOR.

Patented June 5, 1945 HEARING AID Roger S. Wyckoff, Omaha, Nebr.,assignor 01' onethird to Laurens Williams, Omaha, Nebr.

Application June 26, 1942, Serial No. 448,523

8 Claims.

This invention relates to a new and improved hearing aid, and moreparticularly to such a device so constructed as to give an improvedquality of reception.

Hearing aids of the character to which the present; inventionparticularly applies comprise an ear piece fitting closely into the earof the user,

an electrically operated receiver connected to the ear piece. atransmitter or microphone, and electric or electronic means, which mayinclude an amplifier, connecting the microphone and receiver andproviding the operating current for. the receiver. The particularconstruction or design of the microphone and electric or electronicmeans and the operating structure of the receiver'form no part of thepresent invention and will not be described in detail, as manycommercial constructions are available.

Th usual form of receiver is of the magnetic type, although crystal andother types are used. It comprises essentially a relatively smallhousing containing a diaphragm which is electrically operated bymechanism in the housing by a variable electric current transmitted overwires connecting the receiver to the microphon and operating oramplifying mechanism. This receiver has an opening communicating withthe face of the diaphragm, the opening being surrounded by a tubularextension or post by means of which the receiver is connected 'to theear piece. This post is substantially rigid and may be formed of metalor other suitable material. The ear piece is normally formed to fit theconvolutions of the concha oi the ear and to have an extension whichfits into the auditory canal and terminates adjacent the ear drum. Theear piece is provided with a recess into which the receiver postextends, and a sound opening passes from the recess through theextension of the ear piece to terminate adjacent the ear drum. A commonform of securing means for connecting the receiver post and the earpiece comprises a peripheral groove on the post and a coacting splitring carried within the ear piece recess. This and other generallysimilar constructions are used which afford a satisfactory mechanicalconnection, but which are not efllcient in preventing passage ofundesired sound waves.

It is found in actual practice that it is important to prevent thetransmission of air borne sound waves through the connection between thereceiver and ear piece in either direction. The microphone is often wornby the user somewhat closely adjacent the receiver mounted upon the ear.Vibrations from the receiver, if they escape and impinge upon themicrophone, may cause what is known as feed back, which causes a shrillwhistle or howl in the receiver, or, in some cases, a rattle or otherrecurrent noise. Such sounds are objectionable both to the user and topersons of normal hearing who may be adjacent the user. Consequently,sound should be prevented from entering or leaving the ear piece cavitywith the exception of the entranc from the passage in receiver post ofthe desired sound. Extraneous sound, even if not sufficient in amount Ior of a frequnecy to cause actual feed back, can

confuse and distort sound it is desired to transmit.

It is an object of the present invention to provide a new and improvedhearing aid construction comprising separate ear and receiver membersand affording more efficient transmission to the inner ear of thewearer.

It is an additional object to provide a device of this character whichminimizes sound leakage between the elements of the device and furtherminimizes resonance and undesired vibrations of the elements.

It is also an object to provide a construction by means of whichexisting devices may be modified to embody the advantages of theimproved device.

It is a further ob ect to provide a device which is simple in design andconstruction and adapted for commercial production and use.

Qther and further objects will appear as the description proceeds.

I have shown a preferred embodiment of my invention in the accompanyingdrawing, in which Figure 1 is a side elevationof the assembled device;

Figure 2 is a view of the ear piece of Figure 1 e as seen from theright;

Figure 3 is a section taken on line 3-3 of Figure 2;

Figure 4 is a perspective view, on an enlarged scale, of the cushioningand sound excluding washer;

Figure 5 is a fragmentary view showing a m'odified form of construction;and

Figure 6 is a view similar to Figure 5 and showing a furthermodification.

In the drawing, referring first to Figures 1 to 4, the receiver I l isshown as provided with a tubular metal post l2 having a circumferentialgroove 13 to receive a snap ring [4. This ring I4 is carried by theinserted ring l5, which is permanently secured to the ear piece It. Thisear piece is shaped to conform to a portion of the concha of the ear andis provided with a horn ll whichextends into the auditory canal toterminateadjacent the ear drum of the wearer. The horn i? is formed witha sound passage i8 extending therethrough and communicating with thespace adjacent the opening surrounded by ring II and thus with theopening in the tubular post I! of th receiver. This space receives thesealing and sound trapping washer it, which has an inner ring 2U formedof rigid material. The washer l8 may be formed of any soft, resilientand soundor-vibration deadening material, such as sponge rubber,cellulose sponge, felt, or fibre, or the like. The ring 29 may be formedof metal, such as brass, or may be formed of relatively hard or stiffmaterial, such as Bakelite or other synthetic resins. The ring 20 ispreferably thinner than the washer 39 so that it does not contact boththe receiver and ear piece and consequently cannot act mechanically totransmit vibrations. The purpose of the ring 20 is to maintain adefinite. clear passage for the transmission of sound from the receiverto the ear drum, this passage being of a definite and fixed size. If thering were not provided, the opening in the washer would vary in sizewhen installed, depending upon the care of installation and the exactsize of the associated parts, which would cause it to be compressed indiffering degree.

The form of construction shown in Figure differs from that of Figures 1to 4 only in that the washer i9 is fixedly secured to the end of thereceiver post i! by means of cement or other adhesive, as indicated at22. This obviates an danger of the washer slipping out of the cavity inthe ear piece and becoming lost or mislaid when the parts are separated.This construction also has the advantage that the opening in the ring ispermanently and positively aligned with the opening in the receiverpost.

In the form of construction shown in Figure 6, the receiver post 23 hasa circumferential ridge 2% adapted to coact with the snap ring orsimilar securing means carried by the ear piece. The post 23 is alsoprovided with an extended portion 25 about which the cushion washer 2Bis fitted. This washer is similar to the washer is and no inner ring 20is needed in view of the post portion 25. The ridge 24 locates theWasher 28 and compresses it in the ear piece cavity when the elementsare assembled. The washer 28 may be held in place by its resilience orit may be cemented in place as desired.

The washer i8 or 28 is of such size as to be somewhat compressedlaterally when inserted in the ear piece. It is of such thickness thatit is compressed axially when the receiver is assembled upon the earpiece. The washer serves thus to substantially completely seal theconnection between the ear piece and receiver in so far as passage ofsound vibrations or other undesired vibrations inwardly or outwardly atthis point is concerned. The washer also serves to cushion and make firmthe connection between the ear piece and receiver so that any tendencyfor the ear piece to vibrate independently of the receiver is minimized.It minimizes or eliminates any tendency for vibration of the receiver,the receiver post, or the post securing means, and prevents transfer ofvibrations from one element to another. It is thus effective not only inpreventing entrance and exit of sound vibrations which might cause feedback or unwanted noise, but also eliminates any parasitic vibrationswhich would result in disturbance of sounds intended to be transmittedto the user and in reduction of intelligibility of such sounds. With theadvantages referred to, the present invention has the aavmao advantagethat before or after the ear piece has been inserted into the ear thereceiver may be rotatably adjusted relative to said ear piece. Somepersons desire that the cord leading to the receiver enter from the topso that the cord may be run over the top of the ear. Others desire thecord to enter the receiver from the bottom. Some desire it to enter fromthe rear. The use of snap rings to permit rotatable adjustment betweentwo separable conduits is, of course, old, being shown for example inthe patents to Robinson No. 721,- 746, Waters No. 738,503, Spencer No.981,705, Meyer No. 1,754,639 and Blanchard No. 1,771,949.

In addition. the washer serves to largely fill the cavity in the earpiece so as to minimize or eliminate any resonance within the cavity. Bythus eliminating or minimizing all undesired vibrations of the elementsof the device, the undesired entrance and exit of sounds or vibrationsrelative to the sound channels in the parts, and by preventing resonancein the ear piece cavity. the emciency, clarity and fidelity of soundtransmission of the device is substantially increased.

While I have shown certain preferred embodiments of my invention, theseare to be understood to be illustrative only, as it is capable ofvariation to meet differing conditions and requirements, and Icontemplate such modifications as come within the spirit and scope ofthe appended claims.

What is claimed is:

1. In a hearing aid construction, in combination, a receiver having apost extending therefrom and provided with a sound channel, an ear piecehaving a cavity therein to receive said receiver post and having a soundchannel extending from said cavity and terminating upon the inner faceof said ear piece, means operatively associated with said receiver andsaid ear piece for detachably holding said post in said cavity, and anapertured cushioning washer positioned to abut said tubular post withthe aperture in said washer in registration with the tubular channel insaid post and with the channel in said ear piece for preventing leakageof sound at the Junction of said receiver and said ear piece.

2. In a hearing aid construction, in combination, a receiver unit, anear piece unit, said receiver unit having a tubular sound-conveying postextending therefrom. said ear piece unit having a cavity therein forreceiving said post and also having a passage extending therefrom to theextremity of said ear piece unit adapted to be located within the ear ofa wearer, said post and said ear piece unit having cooperating means fordetachably and rotatably connecting them together, and a cushioningwasher located within said cavity having a hole therethrough registeringwith the tubular channel in said post, said cushioning washer beingdisposed in position to be compressed when said receiver unit and saidear piece unit are connected together.

3. In a hearing aid construction, in combination, a receiver unit, anearpiece unit, said receiver unit having a tubular sound-conveying postextending therefrom, said ear piece unit having a cavity therein forreceiving said post and also having a passage extending therefrom to theextremity of said ear piece unit adapted to be located within the ear ofa wearer, said post and said ear piece unit having cooperating means fordetachably and rotatably connecting them together, and a cushioningwasher located within said cavity having a hole thsrethrough registeringwith the tubular channel in said Dost. said cushioning washer beingdisposed in position to be compressed when said receiver unit and saidear piece unit are connected together, said cavity and said washerhaving sizes such that said washer is compressed laterally when insertedin said cavity, said washer having therein a tubular rigid portion tomaintain an opening of predetermined diameter.

4. In a hearing aid construction, an ear piece unit having a horn forextending into the aural cavity and having a sound conducting passagetherein, said unit having a cavity communicating with said passageway,and an apertured cushioning washer located within said cavity andadapted to be engaged and compressed by a sound conducting post of areceiver unit.

5. In a hearing aid construction, a receiver unit having a soundconducting post extending therefrom and adapted to be inserted into anear piece unit, and an apertured cushioning washer located upon saidpost coaxially with said post and adapted to be compressed when saidpost is disposed in operative position in an ear piece unit.

6. In a hearing aid construction, in combination, a receiver unit, anear piece unit, each of said units having a sound passage, and anapertured cushioning washer in abutting relationship to said units, withthe aperture in said washer in registration with said passages wherebysaid washer serves to minimize leakage of sound at the region betweensaid units.

7. In a hearing aid construction, in combination, a receiver unit and anear piece unit, one of said units havin a post extending therefrom, saidpost being provided with a sound channel and being adapted to extendinto the other of said units, said other unit having an aperturedcushioning washer positioned to abut said post, with the aperture insaid washer in registration with said channel in said post andcommunicating with the interior of said receiver unit whereby saidwasher serves to minimize leakage of sound at the junction of saidreceiver unit and said ear piece unit.

8. In a hearing aid construction, in combination, a receiver unit, anear piece unit, each of said units having a sound passage, and anapertured cushioning washer in abutting relationship to said units, withthe aperture in said washer in registration with said passages wherebysaid washer serves to minimize leakage of sound at the region betweensaid units, said annular washer having a substantially rigid tubularmember fitted in the hole therein to maintain an opening ofpredetermined diameter when said washer is compressed.

ROGER S. WYCKOFF.

